This invention relates to laryngeal mask assemblies.
It is common practice to use an airway known as a laryngeal mask for administering anaesthetic and ventilation gases to a patient. These airways comprise a tube with an inflatable mask or cuff at one end, the tube being inserted in the patient""s mouth so that one end is located in the hypopharynx and so that the mask forms a seal in this region with the surrounding tissue. Laryngeal masks are described in, for example, U.S. Pat. Nos. 5,355,879, 5,305,743, 5,297,547, 5,282,464, GB 2267034, U.S. Pat. Nos. 5,249,571, 5,241,956, 5,303,697, GB 2249959, GB 2111394, EP 448878, U.S. Pat. No. 4,995,388, GB 2205499, GB 2128561, GB 2298797 and GB 2334215.
Laryngeal masks have several advantages over endotracheal tubes, which are longer and seal with the trachea below the vocal folds. One potential problem with laryngeal masks is that there is a risk that they may be blocked by the epiglottis during insertion.
It is an object of the present invention to provide an alternative laryngeal mask assembly.
According to the present invention there is provided a laryngeal mask assembly comprising a tube and a mask at the patient end of the tube, the mask including a sealing cuff adapted to seal in the region of the hypopharynx, the cuff extending in a substantially oval configuration and being inclined relative to the axis of the tube, and the cuff enclosing a central region of generally oval shape, the assembly including a blocker member having a plate member at the patient end of an elongate member, the plate member extending generally laterally across the mask to restrict entry of the epiglottis during insertion, and the elongate member extending longitudinally along the assembly such that the blocker member can be removed by pulling rearwardly on the elongate member.
The elongate member may be a strip and it may be flexible. The elongate member preferably extends externally along the assembly. An edge of the plate member preferably engages a surface formation, such as a groove, on the mask. The plate member may be of tear-drop shape.
A laryngeal mask airway assembly according to the present invention will now be described, by way of example, with reference to the accompanying drawings.